Transfer speed slower on media bridge vs wifi only

[Jherb]

Hello,
I have an ax86u as the main router running merlin firmware latest version.
I have a laptop with an AX card internally, and also connected by gigabit Ethernet to an ac66b1 in media bridge mode. (running latest stock firmware)

When I transfer a file from laptop to another computer on the internal network, my speeds plummet when I turn on the media bridge router. I'm not sure why. (speeds go from 33MB/s to 7MB/s. see screenshot below)



Some screenshots are below, and I hope this is enough info.

Any ideas would be helpful, and I appreciate the insights from the more experienced.

speed with media bridge router off

speed with media bridge router on

Media bridge router shows strong connection

ethernet is connected at 1Gbps.

 

[L&LD]

Not clear which clients are transferring to each other (from what to what), and what connections they are using.

It also depends on what files you are actually transferring. One large file? Or, many little files?

Iperf shows ideal conditions. Not the variances of the above.

 

[glens]

I tried iperf with media bridge router off and on, and I get the same speeds. I thought it might be the cable, but the router shows connected at 1gig.

This is perhaps the least clear part of your post. Are you saying the iperf speeds raise and lower in keeping with what happens to the file xfers, or that the iperf speeds stay the same with / without the bridge active? Your concern makes less sense if it's the latter, but I have to ask.

Please flesh out the laptop connectivity during the test segments, and to /what/ (and /how/ the /what's/ connected) you're testing.

Beyond that, more info regarding wifi settings on the routers would be helpful.

 

[Jherb]

Sorry for the sub optimal clarity. I'll try to explain.
In my basement, I have an AX86u as the main router for the house. To this router, I have attached a PC via gig Ethernet.

2 floors up, I have a laptop with an intel AX card. To this laptop, I also have an ac66b1 router set up in media bridge mode connected via gig ethernet. I can toggle this router on or off.

What I do is transfer large files (10gb) from the laptop upstairs to the PC in the basement frequently. Generally, the media bridge router is off and I just use the laptops network card for everyday use. In some occasions, I turn on the media bridge router and hence the laptop then relies on the ethernet to connect through the media bridge.

What I don't understand is why the speeds reduce when going through the media bridge. If I transfer the same file from upstairs laptop to basement PC via laptop's wifi card, I get 30+ MB/s. If I turn on the media bridge so the laptop defaults to its ethernet connection to the bridge, I get 7MB/s for the same file transfer. Nothing else is connected to the media bridge for testing.

In my troubleshooting, I tried to rule out the ethernet cable to the media bridge. As the screenshot shows, the upstairs laptop is connected to the bridge at 1Gbs.
I tried to rule out if it was anything specific to this one file, but all files do the same thing.

Given the feedback given above, I reran the iperf from the upstairs laptop to the PC in the basement running as a server:

speeds with media bridge on

speeds with media bridge off and relying on laptop wifi only

I'm not sure what else to troubleshoot. The media bridge seems to slow things down significantly.

I don't have any special settings on either router. Nothing extra is turned on like QoS, etc. Just a very basic setup.

Sometimes, I want to be able to connect other laptops to the media bridge as well for file transfers, but if the speed is so slow, it's not useable.

I hope this is a little clearer. I really appreciate your help.

 

[L&LD]

Thank you for the additional info. It took some deciphering, but I think I got it now.

If your RT-AC66_B1 router is in Media Bridge mode, it cannot be connected via Ethernet cable.

If you mean the laptop is connected to the Media Bridge and the performance is worse, then that means the Media Bridge isn't optimally placed (in relation to..), or placed too far from, or connecting on the wrong Band, from the main router.

If you are leaving the WiFi connection of the laptop 'on', and simply turning on the Media Bridge, yes, the laptop is getting confused which connection to use. Either turn off the WiFi on the laptop, before you power on the Media Bridge. Or, simply Restart the laptop (do not shut it down, then power it up again, there is a difference on Windows machines) to have it use the wired connection exclusively/properly.

With a 10GB file, you should be maxing out your connection (so, we're good there).

If all of the above suggestions don't help (switching between WiFi and LAN cable on the laptop, checking Media Bridge band used, etc.), and if moving/relocating the Media Bridge to better capture the main router's signal doesn't help, and if adjusting the antennae in a \ | / pattern (when looking at the Media Bridge router from above (and they should be angled in such a way to be perpendicular to the main router's antennae in the basement), then all that is left to conclude is that the laptops AX card is superior to the AC class Media Bridge you're using.

You can also try/test adjusting the main router's antennae, also. (You want them more perpendicular to the area you're wanting better signal to). For example:

Looking at the side view of the home:

| | | --------------------- | |
left is router antennae and to the right is the client (on the same floor)


------------------------ | |
\ \ \ -------------------
bottom, left is router antennae, and to the right is the client on the floor above


/ / / -------------------
------------------------ | |
top, left is router antennae, and to the right is the client on the floor below


The above are only approximate 'ideals'. Adjust as necessary.


Hope this gives you enough to find/fix your issues.

 

[Jherb]

Thank you for the additional info. It took some deciphering, but I think I got it now.

If your RT-AC66_B1 router is in Media Bridge mode, it cannot be connected via Ethernet cable.

If you mean the laptop is connected to the Media Bridge and the performance is worse, then that means the Media Bridge isn't optimally placed (in relation to..), or placed too far from, or connecting on the wrong Band, from the main router.

If you are leaving the WiFi connection of the laptop 'on', and simply turning on the Media Bridge, yes, the laptop is getting confused which connection to use. Either turn off the WiFi on the laptop, before you power on the Media Bridge. Or, simply Restart the laptop (do not shut it down, then power it up again, there is a difference on Windows machines) to have it use the wired connection exclusively/properly.

With a 10GB file, you should be maxing out your connection (so, we're good there).

If all of the above suggestions don't help (switching between WiFi and LAN cable on the laptop, checking Media Bridge band used, etc.), and if moving/relocating the Media Bridge to better capture the main router's signal doesn't help, and if adjusting the antennae in a \ | / pattern (when looking at the Media Bridge router from above (and they should be angled in such a way to be perpendicular to the main router's antennae in the basement), then all that is left to conclude is that the laptops AX card is superior to the AC class Media Bridge you're using.

You can also try/test adjusting the main router's antennae, also. (You want them more perpendicular to the area you're wanting better signal to). For example:

Looking at the side view of the home:

| | | --------------------- | |
left is router antennae and to the right is the client (on the same floor)


------------------------ | |
\ \ \ -------------------
bottom, left is router antennae, and to the right is the client on the floor above


/ / / -------------------
------------------------ | |
top, left is router antennae, and to the right is the client on the floor below


The above are only approximate 'ideals'. Adjust as necessary.


Hope this gives you enough to find/fix your issues.

Thanks for the info. To clarify, the router is in media bridge mode and is connected to the laptop via ethernet. It is connected wirelessly to the main router in the basement on 5ghz band.
Below is a screenshot of the band and link rate. Doesn't this mean its a good connection? Or am I misunderstanding.
Appreciate your tips, and will try to tinker a bit.

 

[L&LD]

Your screenshots look good. Ideally, you should be reaching at or above ~500Mbps transfer speeds.

Does your laptop have an SSD?

Does your PC that you're transferring the file to use an SSD?

What other variables might we be missing?

Try turning on the Media Bridge mode and leaving it on (why are you turning it off?). Disable the WiFi on the computer. Then, plug in the Ethernet cable from the Media Bridge. Are the speeds improved?

If things don't improve, then the next step I would try is testing different Control Channels for the 5GHz band. One at a time. For an extended period (with all your devices and at all important locations within your home). You'll find one that just 'pops', if you are not using it already.

 

[Jherb]

Your screenshots look good. Ideally, you should be reaching at or above ~500Mbps transfer speeds.

Does your laptop have an SSD?

Does your PC that you're transferring the file to use an SSD?

What other variables might we be missing?

Try turning on the Media Bridge mode and leaving it on (why are you turning it off?). Disable the WiFi on the computer. Then, plug in the Ethernet cable from the Media Bridge. Are the speeds improved?

If things don't improve, then the next step I would try is testing different Control Channels for the 5GHz band. One at a time. For an extended period (with all your devices and at all important locations within your home). You'll find one that just 'pops', if you are not using it already.

Yes, both pcs have ssds. And I'm transferring the same file from the same machines to reduce as many variables as I can.

I tried disabling the wifi on the computer, and restarting as you suggested. Didn't change anything.

Regarding your suggestion to change the control channel, that's done from the main router, correct?

 

[L&LD]

Yes, from the main router's Wireless tab.

Can you give a rough diagram of how the equipment is located in 3D space for us to visualize it better?

 

[Jherb]

I'm no

Yes, from the main router's Wireless tab.

Can you give a rough diagram of how the equipment is located in 3D space for us to visualize it better?

I'm not sure exactly what to describe, but I'll try.

The basement router is almost directly below the media bridge vertically (but is 2 floors separated). I oriented the antenna as you said \ | / on both routers.

I changed the control channel, and the media bridge shows the below. Unfortunately, the transfer speeds didn't change though. It looks like its connected with good signal strength, so I'm not clear what is happening.

 

[L&LD]

With the newly orientated antennae, what speeds does the laptop get with its AX card?

Routers (and/or clients) stacked on top of one another (on different floors) are not ideal because of the 'donut' shaped radiation pattern the mostly omnidirectional antennae use.

How far away can you put the routers in relation to each other? So they're not 'stacked'?

--------------------------------------------------Media Bridge
-----------------------------------------------------------------
Main Router---------------------------------------------------



The diagram above (viewed from the side of the home) is more ideal than:

Media Bridge--------------------------------------------------
-----------------------------------------------------------------
Main Router---------------------------------------------------

 

[Jherb]

OK, there is progress but I can't explain it.
I looked at all my settings, and changed the below. It was on wpa2/wpa3 personal. I changed it to wpa/wpa2 personal.

Now the media bridge is roughly twice as fast as the ax card. So it seems like its resolved, but I don't know why.

media bridge file transfer

AX card only file transfer

 

[L&LD]

Because AC class hardware doesn't understand WPA3.


This is also the reason why matched routers (at least same-class routers...) are always the best-performing and most stable within a given network.

 

[Jherb]

Because AC class hardware doesn't understand WPA3.

I guess not I thought it would choose what was appropriate. Its an amazing difference now. It peaks at 64MB/s now with the same file.

Thanks so much for your help and pointing me in the right direction.

 

[L&LD]

You're welcome.

Nothing 'auto' ever works properly in my experience (particularly on consumer routers). Take control and see the differences possible!

 

[glens]

Now the media bridge is roughly twice as fast as the ax card.

Well, we were working toward the router settings and you beat us to it. Good job. Enjoy your setup.

 

[L&LD]

Btw, @Jherb, I would still be trying/testing for the best Control Channel now. You may see similar jumps in performance too.

 

[glens]

By the way, I have a similar situation in that my router is in the basement while the aux. unit is upstairs. The router can pick just about any channel, as it sees next to nothing else on the air, while the aux. unit clearly sees all the neighbor's signals and channel choice can be much more critical for it.

 

[Jherb]

I will try the different control channels to see if there is further improvement. What would be the theoretical max here? I'm getting over 60MB/s now so I'm curious what the limit is for an AC class media bridge.

Thanks so much L&LD, and glens for taking the time to respond and clue me in. The detective work ultimately helped, as I would have never thought the WPA would be an issue.

 

[L&LD]

While your connection rate of 1,300 Mbps I the max, it doesn't mean the throughput can't be improved depending on the CC chosen.

Of that 1,300 Mbps connection, you may get up to ~70% under ideal conditions, so that can be in the neighborhood of ~900Mbps (or, ~ 113MB/s (GbE) speeds, half duplex - not quite 1GbE LAN speeds which are full duplex).

L&LD

www.snbforums.com

See the link above for the Control Channel setup guides.